In punycode.js there is a global const "base", apperently somewhere in the code this is already defined so it throws a js exception and this causes problems in angular because it cannot find a punycode method. I'm not a js developer but a quick grep pointed me towards angular-ui-router. This causes the mail body not too show when you click on a mail in the webinterface or try to create a mail.

Locally I fixed this by replacing base by base2 in the punycode sourcecode. But since it is a vendor script I guess this should be fixed upstream, base is just a too common name for a global constant imho.